Dr Richard Wilkie and
Dr Callum Mole
University of Leeds, Arup and
Transport for London
Truck Safety Conference 2016
In the EU 4,254 people died in
collisions involving heavy
goods vehicles (HGVs) in 2011
28% of road deaths following
HGV collisions were
Vulnerable Road Users 15% pedestrians
7% cyclists
6% powered two-wheeled
vehicles
Accident Statistics
Project Purpose & Aims
• There are currently NO research studies
examining whether Direct Vision of
vulnerable road users could improve road
safety.
• OUR MAIN QUESTION:
Does Direct Vision (windows) enhance road safety compared to Indirect Vision (mirrors) ?
Vision is critically important when driving!
Traditional Cab Low-entry Cab
Indirect
Direct
Mirror Image
Mirrors provide useful visual information not directly visible to drivers.
However, there are potential safety issues:
Mirrors can distort reflected objects
Reflected objects may be overlooked compared to direct
objects
Recognition rates compromised near
mirror edges
Mirrors may be set up incorrectly,
impairing coverage
View can be influenced by
elements such as rain and dirt
Our Focus
Our Research
Three ongoing experiments :
1. Reacting to Visual Objects• Direct vision – via windscreen• Indirect vision – via mirrors
2. Driving and Braking• Traditional vs. Low-entry cab
3. Added Cognitive Load• Reacting to Visual Objects• Traditional vs. Low-entry cab
Laboratory Set-up: Virtual City Driving
Laboratory Set-up: Mirror positioning
Task Design: High Visibility
High Visibility
Task Design: Low Visibility
Low Visibility
Task Design: Pedestrian
Pedestrian
Experiment 1: Reaction Times
The results showed that direct vision responses were on average 0.7s
faster than indirect vision.
RT doubled
What would this delay mean?
Speed Extra Travel
15mph (24km/h) 4.7 m
10mph (16km/h) 3.1 m
5mph (8km/h) 1.5 m
At slow (15mph) driving speeds this would cause 4.7m of extra travel before
braking. At 5mph (pulling off speed) this still equates to 1.5m extra travel.
These distances are more than enough to collide with a pedestrian in front of
the vehicle.
Experiment 2: Pedestrian Collisions
To assess if slower Reaction Times in Experiment 1 would lead to more
collisions, we examined driving when pedestrians crossed the road in front of the
vehicle.
Low-entry cab
Traditional cab
Indirect
Direct
Low Traditional
Entry
% D
RIV
ER
S C
OL
LID
ING
Experiment 2: Pedestrian Collisions
We analysed driving when pedestrians crossed the road in front of either a Low-
entry cab or Traditional cab.
Do slower Reaction Times mean more collisions in city driving?
Yes. The Traditional cab increased
incidence of pedestrian collision by
23%.
Experiment 3: Added Cognitive Load
Drivers usually perform other tasks when driving that can be distracting.
Experiment 3 examined the
impact of a concurrent task on
Reaction Times and Collisions.
As previously Direct and Indirect
vision (or Traditional/Low-entry
cab) conditions were examined
independently.Respond when
BOTH numbers odd
Experiment 3: Added Cognitive Load
Experiment 3: Added Cognitive Load
Does cognitive load slow Reaction Times?
Yes. Cognitive load slowed Reaction Times by an additional 0.5 seconds
(for both Direct and Indirect vision)
+0.5s
Experiment 3: Added Cognitive Load
Does cognitive load impact on collisions?
Yes. Proportion of drivers colliding with
pedestrians increased by 40% in the
Traditional cab when cognitively loaded
(Exp.2) (Exp.3)
No Cog Cog
Low Entry
Traditional
% D
RIV
ER
S C
OL
LID
ING
Summary of Findings
Indirect Vision
(via mirrors
as opposed to
windows )
0.7 sec slower
reaction time
1.5 m increased
distance prior to
braking
(at 5 mph )
Potential
23%increased
likelihood of
collision
Objects /VRUs
overlooked in
mirrors
Gaze
and/or
attention
toward
road
Potential but
undetermined
causes
likelihood of
collision
Cognitive Load
Potential
increased
likelihood of
collision
0.5 sec slower
reaction time
1.1 m increased
braking
(at 5 mph)
distance prior to
40%
Further Details
• These are preliminary
research findings
• End of project report
submitted to TfL
14/10/2016 In collaboration with:
Funded by: